Tybee has a designated 8-mile stretch of marked & signed bike route, 2 of those miles actually dedicated as a "bicycle boulevard" (2nd Avenue). For more information & the Bicycling on Tybee Island Map (scroll down to the bottom of the page), please click the link below:
http://www.cityoftybee.org/
As you will see, there are bike racks at all beach entrances & you will find that many restaurants/businesses will have them too. Bicycling is a great way to see the Island and get in that daily recommended 30 minutes of moderate physical activity needed to maintain a healthy lifestyle.